General Grievous is a villain from the Star Wars fictional universe. He is the leader of the droid armies of the Confederacy of Independent Systems and an enemy of the Jedi. His physical body is a fusion of a powerful robotic structure and an organic brain, nervous system and sensory organs. Another interesting fact about him is that he nearly killed Boba Fett in a Republic siege of Xagoba. While he was voiced by John Di Maggio in Chapter XX of the Cartoon Network Star Wars microseries, Clone Wars, Richard McGonagle took over the voicing of Grevious for the rest of the micro series, and Matthew Wood voices Grevious in Star Wars Episode III: Revenge of the Sith. Dark Horse is currently publishing a 4-part comic about General Grievous.
Grevious was known as a Jedi hunter, killing them for sport and collecting their lightsabers to proudly place around his belt as trophies or use them in his battles. The general possessed strategic ingenuity and flawless cunning. He first revealed himself to the public when he attacked a dispatched a team of six Jedi Knights in an aggressive display of lightsaber mastery (which he learned from Count Dooku) during the Battle of Hypori. With his mechanical enhancements and attributes combined, it made him able to battle five Jedi singlehandly. Only three survived the ordeal from the somehow invinicible foe. The Separatist General began the swift conquest of several Outer Rim planets, much to the dismay of the Republic. Time after time, Grievous' ability to strategize attack plans with brilliant ideas and destructive results made the Republic's star fleet commanders shudder at their knees. Grievous himself, would later resurface during the Battle of Coruscant, using his first wave as a distraction to kidnap Chancellor Palpatine. He killed all Jedi protecting the Chancellor except Shaak Ti, whose lightsaber he took as an addition to his grisly collection. While departing Coruscant Mace Windu badly wounds Grievous using the force.
The General displays amazing dexterity and can fight with four lightsabers simultaneously by dividing his mechanical forearms which each employ two opposable thumbs. Grievous travels with his droid bodyguards, who wield electrified rods used for defense against most weapons (including lightsabers). It will be the first time Star Wars fans have seen an non-lightsaber weapon that can withstand the cutting power of a lightsaber itself (besides certain weapons introduced in Star Wars: Knights of the Old Republic).
Movie Notes
It is said that George Lucas had his team of computer animators hard at work trying to "lock in" the exact look of the new villain, since he is supposed to be 100% CGI. Many new details of his face and body have been overhauled in order for Lucas to be perfectly content.
Background information
Grievous was originally an organic being of the alien race known as the Kaleesh, which was at war with an enemy species known as the Huk. The Republic supported the Huk, and so the Kaleesh ended up getting support from the Separatists and in particular the Intergalactic Banking Clan.
San Hill, leader of the Banking Clan, noticed that Grievous was both a brilliant strategist and an excellent fighter, and asked Grievous to lead the Separatist troops throughout the galaxy against the Republic. Grievous refused, saying that he only cared about the war between the Kaleesh and the Huk, not about the larger conflict between the Separatists and the Republic. Hill brought this to the attention of Count Dooku and Darth Sidious, but despite their offers Grievous still refused to lead the Separatist army.
So Sidious, Dooku, and Hill arranged to have a bomb planted on the shuttle Grievous was on, and blame it on the Republic. Grievous was mortally wounded in the crash, and his unconscious, dying body was taken to the planet Geonosis, where his brain, eyes, and other organs were implanted into a cyborg body forged by Geonosians that would compliment his natural reflexes.
It might have been his rage at the Republic, who he believed caused his shuttle crash; it might have been a feeling of gratitude toward the Separatists for saving his life and giving him a new and improved body; or it might have been the modification that Banking Clan scientists made to his brain while he was unconscious; but when Grievous woke up in his new body he was more than willing to take up Hill's offer and agree to lead the Separatist troops throughout the galaxy against the Republic.
The General's Kaleesh and Droid background render him unable to call upon the Force.